Will Milt Olin ever become a statistic?

September 1, 2015 Leave a comment

Milt Olin died on December 8, 2013 after an L.A. County sheriff struck him from behind. The sheriff was operating a computer while driving, and faced no charges. The sheriff’s department has since revised its operating procedures to limit deputies from driving while typing.

For nearly a year now, I’ve been monitoring the SWITRS data feeds in hopes of seeing how Olin’s death gets entered into the official record. As of today, nearly twenty-one months from the date he died, I still can’t find it. The SWITRS website includes a disclaimer that “data is typically seven months behind the current date” because of processing backlogs. It may be that SWITRS has yet to release its full 2013 records, but the CHP appears to have prepared its 2013 crash reports. For the CHP at least, and for the agencies and government officials that depend on CHP reports, Milt Olin’s death may never serve even the simplest function in improving roads, that of knowing who we kill and why.

A 2011 paper that looked at San Francisco hospital admissions versus SWITRS reports showed as much as twenty-six percent of cycling injuries never hit the official records. How many deaths do we miss as well?

Categories: Uncategorized

One small step: Beverly Hills improves Santa Monica and Wilshire

April 1, 2015 1 comment

The westbound intersection at Santa Monica and Wilshire Boulevard in Beverly Hills is the worst on my ten-mile bicycle commute. It has no crosswalks on its northern side, and its two right-turn lanes from Santa Monica onto Wilshire make it difficult for cyclists going straight on Santa Monica. For years, such cyclists have had to position themselves in the middle of a cacophony of cars. Here’s how it looks on Google Maps:

SMWilshire

All these problems changed this morning. Overnight, the city removed the optional right-hand turn lane and replaced it with space off-limits to motorists. The change is most likely due to the city moving the westbound bus stop from the west side of Santa Monica to the east, requiring that buses have a way of getting back into Santa Monica traffic. That was difficult when there were two right-turn lanes to Wilshire. Now, with a single right-hand lane, the buses can navigate easier.

For me, this means the single most dangerous intersection on my commute has been removed. That wide space on the first photo below, marked by chevrons, is now space where cyclists can stop can breathe a moment.

1) Looking west on Santa Monica Boulevard. Where I’m photographing used to be an optional right turn lane.

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2) Looking east from the other side of the intersection, a bus navigates back into traffic after picking up passengers

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3) After the bus has left the intersection.

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Who’s Dying on California’s Roads?

From 2001 until 2012, the years for which we have full SWITRS data, deaths on California’s roadways have gone from 3,926 to 2,995, a decline of about twenty-four percent. This is the good news. In 2013, a year for which full data isn’t yet delivered, deaths are already running higher than the previous year, at 3,102. The last four years have actually brought much of the same, with gradual year-over-year increases. Before that, deaths had been falling sharply, from 2007 to 2010, perhaps because high fuel prices and the “Great Recession” kept drivers off the roads.

These overall road safety gains have mostly accrued to drivers of motor vehicles, and specifically to drivers of cars and pickups. Vulnerable road users have seen few safety gains at all. Deaths among motorcyclists have risen an astonishing fifty-two percent (295 to 449), and cycling deaths by twenty-six percent (116 to 147). Pedestrian deaths look flat, down by nearly three percent (721 to 701) for the same period, but 2013 is going to be bad for them, according to the preliminary numbers I’ve seen, with 752 total deaths already reported, erasing all gains.

The stats above suffer from one big problem: they don’t have a base rate, they don’t show us per-capita changes. If motorcycle riding increased by fifty-two percent over the years from 2001 to 2012, then the increase in deaths might explainable. I haven’t spent time (on this lazy Sunday) locating base rates, if it’s even possible. But there is one easy way to use this raw data as is to show how savagely vulnerable users have suffered. We can look at the proportion of deaths each category of road user represents, per year, and look at the changes year-over-year.

Here are the proportion of deaths for all major road user categories for the years 2001-2012:

Year Car & Pickup Occupants Motorcyclists Cyclists Pedestrians Others
2001 68.9% 7.5% 3.0% 18.4% 2.2%
2002 68.5% 7.8% 2.1% 10.5% 11.1%
2003 67.7% 8.7% 2.6% 15.0% 6.1%
2004 61.4% 8.5% 3.0% 16.5% 10.6%
2005 61.1% 9.4% 3.0% 17.1% 9.4%
2006 59.3% 10.3% 3.7% 17.3% 9.4%
2007 60.5% 11.7% 3.1% 16.7% 7.9%
2008 56.7% 15.6% 3.7% 18.4% 5.7%
2009 60.5% 12.4% 3.4% 19.3% 4.4%
2010 58.3% 12.7% 4.0% 22.7% 2.2%
2011 55.0% 14.7% 4.9% 23.1% 2.3%
2012 54.9% 15.0% 4.9% 23.4% 1.8%

The motorcyclist death-rate proportion increase is horrible, one-hundred percent (7.5 to 15), but every other vulnerable road user has also seen huge changes. Cyclists proportion of deaths has increased by sixty-three percent, and the proportion of pedestrians dying has increased by twenty-seven percent. Motorists, by contrast, are the sole road users showing a decrease, about twenty percent overall.

I haven’t done the hard work necessary to explain these numbers, but I’d guess car manufacturers are responsible for most of it. That is, fewer people are dying in cars because cars have gotten safer, while vulnerable users have seen no safety improvements. These users need changes in infrastructure and the laws for their safety, and we — our society and government — have done little with our roads or legislation. We haven’t lowered speed limits, improved pavements, bettered sidewalks or bicycle paths or crosswalks, tightened drunk driving standards, or enforced mobile phone restrictions. We’ve done hardly anything. The stats show up the problems: road users who have no access to better automobile technology are dying in ever greater proportions.

Categories: Planning, Policy, Safety

Safest day to cycle?

February 19, 2015 Leave a comment

Here’s a count of all cycling fatalities in California from 2001 to 2012, tabulated by year and day of week. The raw data comes from SWITRS.

Monday Tuesday Wednesday Thursday Friday Saturday Sunday
2001 10 17 18 21 20 21 14
2002 16 16 15 19 26 15 13
2003 19 19 15 20 19 18 15
2004 17 11 13 20 12 17 34
2005 16 21 16 18 18 20 23
2006 17 20 22 23 28 22 23
2007 14 21 23 17 15 21 14
2008 16 19 23 16 20 11 26
2009 18 13 18 7 22 15 16
2010 22 8 10 19 18 14 20
2011 21 14 23 15 22 29 18
2012 21 16 23 26 28 22 16
Totals 207 195 219 221 248 225 232

Is there any knowledge to be gleaned here about the safest day to cycle? One of the biggest problems in analyzing SWITRS cycling data comes from the lack of base rates, or overall counts of cyclists for a given period. The single worst day came from the 34 people who died on Sundays in 2004, but without knowing whether many people were cycling on Sundays in 2004, we can’t determine the rate of fatalities, and there’s not much we can derive about safety from these numbers. In a word, then, we don’t know when it’s safest to ride.

Still, my guess is that cycling rates climb on the weekends. If that’s true, we should expect to see higher fatalities overall on Saturdays and Sundays. They don’t show here in the totals for the weekends, which look rather like the rest of the week. The cause could be as simple as less car traffic on the weekends, or as rich and complex as this notion of safety in numbers, the idea that so many people are cycling on the weekends that drivers notice them.

Ultimately, we really need better information about cycling in California. We don’t know much about ourselves, how many of us ride, when we do, how we get into crashes, and why.

Categories: Safety Tags:

Helmets: Are bad stats leading to bad bills?

February 12, 2015 2 comments

California state senator Carol Liu introduced an all-ages bicycle helmet bill yesterday, much to the dismay of many people who know a thing or two about helmet legislation. The early betting has the bill dying quickly in committee or elsewhere, although in a sense it might be productive to have a full and lively hearing about the merits of bicycle helmets. Some of the dismal, even disastrous, examples from places like Australia and New Zealand — where helmet legislation has apparently had no safety effect while also reducing cycling significantly — might kill these ideas for years to come.

Senator Liu’s press release included this statistical “gem” taken from a report by the National Conference of State Legislatures (NCSL): “Ninety-one percent of bicyclists killed in 2009 reportedly were not wearing helmets.” Since she mentioned it, Senator Liu is apparently relying in some part on this number to make her case. Where does it come from? Does it hold up to scrutiny? Does it reflect the California experience?

The underlying NCSL report doesn’t mention sources, but it’s a pretty safe bet that its numbers are coming from FARS, the federal Fatality Analysis Reporting System. FARS, in turn, gets its data directly from state highway data collection systems, which are implemented at the local law enforcement level. In California, the Statewide Integrated Traffic Records System (SWITRS) plays that role, and its data is open to all comers — including me, as it happens.

Over the past few weeks, I’ve been toying with SWITRS data, trying to understand its structure, and looking into what it might reveal about our roads. I’ve only gotten my feet wet with it so far, and I’ve much to learn, but from what I’ve seen, Liu’s “ninety-one percent” number is problematic. Take the year 2009, the year she singles out for mention. FARS shows 628 total cyclists killed in the U.S. that year. SWITRS tells me that 107 California cyclists were killed in the same year; presumably, those 107 are included in the 628 total. How many of those killed California cyclists were wearing helmets? SWITRS tells me there were twenty-two cyclists wearing helmets, sixty-seven who weren’t, and eighteen unknowns. In other words, in California sixty-three percent didn’t wear helmets — not ninety-one percent, as the nationwide number suggests — twenty-one percent wore them, and for seventeen percent of cycling fatalities we have no data.

My point might be small, but it should be in the mix nonetheless: Senator Liu implies that only eight percent of killed cyclists are wearing helmets, but in California that’s just not the case. More than double the cyclists are wearing them, and even more might be, if we knew more about those many unknowns. The hard facts? Lots of Californian cyclists are being killed despite their helmets, just as other studies show. We need to spend time confronting the real factors, like bad road design, high speed limits, and poor cycling infrastructure if we expect to make a real dent in fatalities.

Where does FARS get that huge ninety-one percent number? I’m not sure yet, but it sure looks suspiciously like they are grouping the unknowns in with the nos. That is a big no-no!

Just for completeness, I went back and extracted the numbers for all the years for which we have full SWITRS data (2001-2012):

Year No Helmet Helmet Unknown No helmet Helmet Unknown
2001 76 17 23 116 66% 15% 20%
2002 78 22 15 115 68% 19% 13%
2003 81 27 18 126 64% 21% 14%
2004 74 27 22 123 60% 22% 18%
2005 75 20 37 132 57% 15% 28%
2006 100 34 21 155 65% 22% 14%
2007 76 25 23 124 61% 20% 19%
2008 73 30 27 130 56% 23% 21%
2009 67 22 18 107 63% 21% 17%
2010 67 24 20 111 60% 22% 18%
2011 81 33 26 140 58% 24% 19%
2012 77 49 20 146 53% 34% 14%

As far as I can see, never in the past twelve years of data has any year approached Senator Liu’s number. Whatever comes of Senator Liu’s legistration, we should make sure that incomplete data don’t lead to bad statistics used to justify bad policy enshrined in unhelpful laws.

Categories: Helmets, Law

Do Dutch women have more time to cycle?

October 12, 2014 Leave a comment

In a puzzling October 3 opinion article published in The Guardian, Herbie Huff and Kelcie Ralph argue that Dutch women cycle more because they have more time than U.S. women. The authors say this extra time comes from different Dutch cultural norms and social policies, along with better city planning that frees women from driving their children school. They conclude that improved cycling and pedestrian mobility in U.S. cities will require deep changes to social policies, ideas with “far-reaching implications and [that] require serious value shifts.”

These are thin arguments with shaky foundations. If U.S. women have less disposable time than Dutch women, Huff and Ralph have not done the hard work of showing it. The paper they cite examines American households, and has nothing to say about how Dutch households allocate their time. There’s no comparative data here, just assumptions and what-ifs. As long as we can invent results, I could say, for instance, that most Dutch fathers use their paternity leave for leisure purposes — say, to play more golf — leaving their partners to handle all household chores with no disposable time left for anything.

But even if we grant them their arguments, Huff and Ralph haven’t shown why giving women more disposable time leads to more cycling. The implicit assumption is head-scratching, that somehow women use their extra time riding bicycles instead of doing something else. How can we assume this about any person or culture? Would the opposite hold — would Dutch women ride less if they had less disposable time? Would time-rich U.S. women suddenly opt to cycle? How do we know that cycling is the go-to activity once women gain more time?

Huff and Ralph don’t tackle counterexamples like New York City, where more than half of households don’t own cars and yet somehow find the time to chauffeur their children around town, all without Dutch social policies to free up time. They also don’t address why U.S. women in child-free couples, and single women without children, are less likely to cycle. They discount surveys where women say straight out that they are afraid on the road — though one wonders why we should second-guess women who presumably say exactly what they mean. And they they don’t tackle the problem of countries with social policies similar to The Netherlands (Norway, Finland) that have low cycling rates.

One of the subtle and insidious assumptions underlying this article is that cycling is primarily a hobby or non-essential activity. In the cited study, cycling comes in for a mild whipping with the unsubstantiated claim that errands are “easiest to do in a private vehicle, and hard to do on a bicycle or public transit;” that is, only those people with extra time on their hands undertake cycling, perhaps because it’s slow. (This assumption came under some small scrutiny in a quick Twitter exchange I had with @JennyGoBike, a car-free mother-of-three in Seattle: “Don’t assume cycling harder til you’ve wrangled 3 tots into minivan. Challenges to both.” ) The Dutch — in my experience more practical and as time-conscious as any American — have created the infrastructure that turns that assumption on its head. The Dutch don’t cycle because they have extra time; they cycle because they have no time to spare. They cycle because cycling is the fastest way to get around.

The way I see it, Huff and Ralph have worked a little too hard to find a link between Dutch social policies and cycling. It may be the case that such policies are superior to American ones in every possible way, but the essential lesson of Dutch cycling does not come from them. It comes, instead, from the city planning and infrastructure build-out that has elevated cycling to a first-class, normal way to get around.

Categories: Dutch cycling, Planning, Policy

Now that we’ve the three-foot law, what’s next?

September 16, 2014 Leave a comment

After years of contention and a rocky path towards passage, California’s three-foot rule finally takes effect today.The law requires drivers to pass cyclists by three feet or more, and penalizes them with a small fine if they fail to comply.

How far is three feet? This will be among the many difficulties of enforcing the new law, and will likely limit its impact. Obviously, if a cyclist actually gets hit, that qualifies as a violation (but then the law won’t have made that cyclist safer); otherwise, it’s a judgment call that any good attorney will turn against the state in court.

How far is three feet? If this new law is to have any teeth, we need to define exactly where the boundary lies. While I’m not a big fan of painted infrastructure, one way to show what three feet means is through “bicycle-priority lanes.” Unlike existing bicycle lanes, which exclude motorized vehicles, bicycle-priority lanes would give first precedence to cyclists and second precedence to all other motorized users. As Peter Furth points out in his paper on the subject, the “magic of lines” comes from the “objective boundary of the bicycle zone” they provide. Drivers would know exactly how far they need to go around cyclists, and cyclists would have a defined place on the road.

Priority lanes are stepping stones towards proper separated bicycle lanes. They may help solve that perpetual chicken-and-egg problem of infrastructure, perhaps inducing a few more cyclists onto the streets, and giving us a few more voices for better facilities.

Categories: Lanes, Los Angeles
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